Grinding Ball Fragments in the milling circuit impact on two critical areas. One is the crushing circuit where companies have observed damage to crushers, unscheduled downtime and loss of production. The other is the grinding circuit where companies have discovered wear to pumps, sumps, piping, hydrocyclones, mill liners as well as inefficient
Read On1. SAG mill is the primary tool for grinding. SAG mill is used before the other mills. Ball mill is a secondary, and it is used after the SAG mill. 2. SAG mill breaks the raw material into pieces for the further grinding. Ball mill is used …
Read OnThe ball-mills in SABC circuits are operated at a relatively high speed (70-78% of critical speed), with large balls (50 mm to 80 mm), to cope with a coarse feed (a transfer size from the SAG mill ...
Read Onin the SAG mill extremely hard in the ball mill. The but significance of this waste sample in determining SAG throughput is that the waste will not impede SAG throughput but will cause a larger circulating load and a slightly coarser final cyclone product in the ball mill circuit.
Read OnAG/SAG mills can accomplish the same size reduction work as two or three stages of crushing and screening, a rod mill, and some or all of the work of a ball mill. Because of the range of mill sizes available, AG/SAG milling can often be accomplished with fewer lines than in a conventional rod mill/ball mill circuit. A diagram of types of AG/SAG ...
Read OnAt 8 – 12 % v/v ball charge volume, and 25 – 35% v/v total charge volume the SAG mill typically draws 10 –. 11 MW. The operating work index for …
Read OnIn the case of SAB/SABC circuits the transfer size is the product of the SAG mill circuit and the feed of the ball mill circuit. Hence if power-based equations such as eq. 1 and eq. 2 are to be used to predict the SAG mill circuit and ball mill circuit specific energies it is important to ascertain:
Read OnSAG mill circuit product size (so-called transfer size P80 or T80 for short) recorded. Operating conditions for the SAG mill such as ball load, speed and % solids were kept . 8 constant as they are during normal plant operation. This was done up to throughputs that
Read OnIt was initially developed for a SAG/ball mill grinding circuit on the gold plant at Paddy's Flat in Western Australia. The aim of the system is to provide a quick reference manual plus immediate on-line advisory help for the shift operators. The on-line help is in the form of an interactive trouble-shooting procedure and a mill power model for ...
Read OnWith more than 100 years of experience in ball mill technology, Outotec ball mills are designed for long life and minimum maintenance. They grind ores and other materials typically to 35 mesh or finer in a variety of applications, both in open or closed circuits.
Read OnPage 769 MINING AND MINERAL PROCESS ENGINEERING, UBC - Vancouver, 6. C. Canada AG AND SAG MILL CIRCUIT SELECTION AND DESIGN BY SIMULATION Dr. S …
Read OnWhere the SAG mill/ball mill circuit is the bottleneck in the processing plant the pebble circuit can be a significant factor in limiting overall plant capacity. The pebble circuit recirculating load can be very significant (depending on the ore …
Read OnIn his approach the total specific energy of the entire AG/SAG circuit is firstly predicted using the SAG mill feed F80 and the ball mill cyclone overflow P80. Morrell's model (Morrell, 2011) relates the feed, mill geometry and operating conditions to the specific energy of the circuit. However, the F80 is not enough to represent properly ...
Read Oncircuit or the overall performance of an autogenous-semiautogenous (AG-SAG)/ball mill circuit, but they are of limited value in evaluating AG-SAG and ball mill sections separately. This problem arises due to the difficulty of describing particle size distributions with different shapes by one number, the eighty percent passing size. This
Read OnFollowing the upgrades in the SAG mill circuit, sampling and modeling of the ball mill circuit identified a bi-modal hardness characteristic of the ore. valuation with both MetCom and JK SimMet®E lead to changes in the ball make up size from 75 …
Read Onconsidered, such as a primary SAG and secondary ball mill circuit where the individual stages would be ESAG and Eball, and the combined total circuit CEE would be Etotal. In all cases, the specific energy consumption is defined as the motor power consumed relative to …
Read OnThe biggest characteristic of the sag mill is that the crushing ratio is large. The particle size of the materials to be ground is 300 ~ 400mm, sometimes even larger, and the minimum particle size of the materials to be discharged can reach 0.1 mm. The calculation shows that the crushing ratio can reach 3000 ~ 4000, while the ball mill's ...
Read Onsemiautogenous grinding (SAG) mills and is the fourth paper in a series of five papers on Inferential Measurement of SAG Mill Parameters. The development of the inferential measurement models of SAG mill discharge and feed streams and mill rock and ball charge levels, detailed earlier in the series, is summarised.
Read OnCircuit surveys reported a SAG specific energy of 8.6 kWh/t and ball mill specific energy at 8.0 kWh/t (Dunne et al, 1999 Hart et al, 2001). The T 80 was not given so this was back-calculated to ...
Read Onthe HPGR - ball mill circuit achieved a 21% reduction in energ y consumption over the existing SAG - ball mill circuit at the same P 80 grind size of 160 µm. At a grind of 80% passing 75 µm, the HPGR - stirred mill circuit showed a 34% reduction in energy compared to the base case. It was concluded that the energy
Read OnAmelunxen SGI Model. This is a model that estimates the specific energy consumption of a SAG or AG mill plus ball mill circuit using the equation by Amelunxen (2014) for E SAG and the classical Bond work index equation for E …
Read Ondesign processing rates of the Cadia Hill SAG mill circuit and that could be easily manipulated were; SAG Mill Load Ball Charge - SAG mill power draw was guaranteed by the vendor at 13% ball charge and 30% total volume to be 20.96MW for the 40 foot diameter SAG mill. In practice this power draw was never achieved I-14 (Dunne et al 2001).
Read Oncrushed ore is fed into a SAG/Ball mill circuit with a median size of approximately 12,000 microns. Most SAG Mills are operated in closed circuit with a screen. The screen fi lters undersized ore, normally minus ½ inch, to a ball mill discharge sump. The combined mill discharg-es are pumped to undergo classifi cation, normally via hydrocyclones.
Read OnCompany Project Circuit Type Mill Size (m) Power (MW) 2001 Dia. x EGL Newcrest Cadia SABC 12.2*6.10 20 WMC Olympic Dam S/S AG 11.43*7.62 18 Pasminco Century SAG-Ball 10.97*5.41 12 KCGM Fimiston SABC 10.97*4.27 12 MIM/Investco Ltd. Ernest Henry SAG-Ball 10.4*5.10 11 Total MW 73 1996
Read OnSAG milling extends itself to many applications due to the range of mill sizes available. They can accomplish the same size reduction work as two or three stages of crushing and screening, a rod mill and some or all of the work done by a ball mill. SAG mills are also an optimum solution for wet grinding since crushing and screening in these ...
Read Oncircuit, comprised of a 6.1 m diameter x 2.74 m long SAG mill and a 4.1 m diameter x 5.5 m long secondary ball mill in closed circuit with cyclones, was built using SAG Power Index and Bond Ball Mill Work Index testing to determine the grinding energy requirements.
Read Onproposed flowsheet consists of existing SAG mill circuit followed by a new proposed ball mill in closed circuit with the existing hydrocyclone package. In all simulations, SAGT, CYCL and MILL models were selected to simulate SAG mill, Hydrocyclone packages and ball mill units. SAGT and MILL models both are based on the population balance model ...
Read Oncircuit is shown in Figure1. It is commonly referred to as a SABC circuit, for Semi-Autogenous Ball mill Crusher (SABC). This circuit shows a semi-autogenous grinding (SAG)/ball mill circuit where both grinding mills are in closed circuit, with the SAG mill closed with a crusher to control the amount of 'critical size' material in the circuit.
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